Why are the subjects usually dropped from sentences before the conjugated verb?

Because the pronoun is implied in the conjugated verb. Use the pronouns only when you want to clarify, give emphasis, or contrast.

navegar por la red

surf on the web

A qué hora?

At what time?

Saludos: Tú

amigo/a, compañero/a

Hola!, qué tal?
or
Hola! cómo estás?

Dónde vs. Adónde.

The question word dónde simply means where? and is used to inquire about location. However, you will use adónde (to where?) with verbs such as ir (to go) to indicate movement from one place to another.

Como están su familia?
Como están tu familia?

How is your family? (Ud.)
How is your family? (Tú)

All days of the week are masculine and are not capitalized. Notice the difference in meaning between use of their plural form and use of their singular form.

Hours of the clock are feminine and, with the exception of a la una, are always given with the plural article las.

A las diez, a la una

inglés

English

Qué quiere decir "lo siento?"

Quiere decir "I'm sorry."

nouns ending in -ista, and almost all ending in -e do not change.

They keep the same form, whether referring to a male or a female.

Cómo ...?

how?

la biblioteca

library

Possessive adjectives agree with the nouns they modify, not with the possessor.

The possessives mi/mis, tu/tus, and su/sus do not have separate feminine forms.

Since the possessive su and sus can refer to his, her, their, or your (Ud. and Uds.), their meaning depends on the context.

making nouns plural: add nothing to the final -s

los lunes

Cuántos? o Cuántas?

How many?

literatura

literature

Cuándo vs. a qué hora?

Whereas in English, the question when? can be used to inquire about anything related to time, Spanish uses the question a qué hora? at what hour? whenever the inquiry is about the hour of day, or clock time.

masculine plural

muchos, buenos, pocos, grandes, populares, mis

Perdón.

Está bien.

los jueves

every thursday

Por qué? Notice that the question why? is two words.

The response to por qué is porque, one word, with no accent.

Not all nouns ending in -ma are masculine however, learn the following since they are very frequently used:

el idioma, el sistema, el problema, el tema, el programa, el diagrama

los lunes

every monday

Because numbers already indicate plurality, they have no separate plural forms.

una clase, cinco clases, dieciséis alumnos, veinte mochilas

al restaurante

to the restaurant

feminine plural

muchas pruebas

el centro de estudiantes

student union

masculine plural

muchos chicos

comer algo

eat a little bit

Nouns ending in -z are made plural by changing the -z to -z and adding -es

lapiz -> lapices

casa

room

To refer to a group composed of both masculine and feminine persons, use the masculine plural form: